David,
thanks for the response.
Here is a code snippet and the accompanying error messages from Xerces
and Internet Explorer.
I believe you may be correct...I am trying to impose restrictions on
character
data...ensuring it is either a BUY or SELL code.
====================================my program======================
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE DOCUMENT [
<!ELEMENT transaction_file (transaction)* >
<!ELEMENT transaction (code)>
<!ENTITY % validCodeEnum "BOUGHT|SOLD">
<!ELEMENT code (%validCodeEnum;)>
]>
<!--notice second record has code=LEASE-->
<transaction_file>
<transaction>
<code>BOUGHT</code>
</transaction>
<transaction>
<code>LEASE</code>
</transaction>
</transaction_file>
====================================Xerces error======================
C:\xerces\java sax.SAXCount -v d:\Temp\petest.xml
[Fatal Error] petest.xml:6:17: A '<' character or an element type is
required in the
declaration of element type "code"
org.xml.sax.SAXException: Stopping after fatal error.....
====================================from IE======================
The XML page cannot be displayed Cannot view XML input using style sheet.
Please correct the error and then click the Refresh button, or try again
later. Parameter entities cannot be used inside markup declarations in an
internal subset. Line 6, Position 16 <!ELEMENT code (%validCodeEnum;)>
---------------^
Tom
> ----------
> From: David Bourget[SMTP:[EMAIL PROTECTED]
> Sent: Wednesday, April 19, 2000 12:15 PM
> To: [EMAIL PROTECTED]
> Cc: [EMAIL PROTECTED]
> Subject: Re: Resend - can ELEMENTS reference ENTITIES?
>
> Hi Tom,
>
> > I am having some trouble with enumeration in XML.
> >
> > Rather than doing this,
> >
> > <!ELEMENT TxnCode (BUY|SELL|DEP|INT)>
> >
> > I need to do the following, but it seems to be invalid,
> >
> > <!ENTITY % validCode "BUY|SELL|DEP|INT">
> >
> > <!ELEMENT TxnCode (%validCode;)>
>
> I see two possible issues here
>
> 1- If Xerces-* does not allow you to use a PE in that context, then this
> is
> a bug.
>
> 2- If Xerces-* tell you that you are doing something wrong but that this
> entity reference is well placed that's because you can't define
> restrictions
> on the character data of an element in a DTD. The construction you are
> using
> defines the content model of your element, but it seems that you have not
> defined those children elements. I strongly suggest that you use an
> attribute as they are really meant to fill the purpose *I think* you are
> describing here. However, there is a way to achieve the same result in
> using
> elements :
>
> <!ELEMENT BUY EMPTY>
> <!ELEMENT SELL EMPTY>
> <!ELEMENT DEP EMPTY>
> <!ELEMENT INT EMPTY>
>
> <!ELEMENT TxnCode (BUY|SELL|DEP|INT)>
>
> Using it will result in :
> <TxnCode>
> <BUY/>
> </TxnCode>
>
> An other solution would be to use schemas.
>
> I hope this help,
> David
>
>
>
